The objective of this project is to provide assistance to the Organization of a Network of Quality Control Laboratories for Vaccines in Latin America as part of the program for a Regional System of Vaccines (SIREVA). During FY92, the following items and support were provided to SIREVA. . Master cultures of B. pertussis 18323 for use in establishing a seed lot system of cultures to be used in the intracerebral challenge of pertussis vaccine mouse potency assays. . Methods for propagating, freeze-drying and maintaining a seed lot system provided in English, Spanish and Portuguese. . Methods for the intracerebral challenge mouse potency assay provided in English, Spanish and Portuguese. . 4000 vials of freeze dried vaccine to be used as the Working Standard Pertussis Vaccine for the Western Hemisphere. . Details manufacture, freeze drying and standardization of the Working Standard Pertussis Vaccine. . Results of preliminary pertussis vaccine potency assays to determine the unitage contained in the Working Standard Pertussis Vaccine. . Proposed protocol for collaborative assays of the Working Standard Pertussis Vaccine to validate and confirm the number of protective units contained therein. . 50 vials of the International Standard Pertussis Vaccine, Lot No. 2. . Computer programs specifically designed to calculate vaccine potency and related laboratory assays, supplied under two operating systems (DOS and Mac) and in three languages with appropriate documentation on applications and instructions for use. . Methods for the freedom from toxicity for pertussis vaccine. . Methods and computer programs for the randomization of bioassays in general and pertussis vaccine provided in English, Spanish and Portuguese.